Heat dissipation device

ABSTRACT

A heat dissipation device for removing heat from a heat-generating component, includes a base and a fin group arranged on a top of the base. The base includes a conducting plate, a retaining bracket attached to a bottom surface of the conducting plate, a plurality of heat pipes located between the conducting plate and the retaining bracket and a heat absorbing block embedded in the retraining bracket. The heat pipes have first portions arranged side by side closely and sandwiched between the conducting plate and the retaining bracket and second portions bent from the first portions away from the retaining bracket in a divergent manner. The heat absorbing block has a top surface in contact with the heat pipes and a bottom surface for contacting with the heat generating component.

BACKGROUND

1. Technical Field

The present disclosure relates generally to a heat dissipation device,and more particularly to a heat dissipation device having heat pipesincorporated therein.

2. Description of Related Art

Computer electronic components, such as central processing units (CPUs),generate a mass of heat during operation. If the heat is not removedquickly, it may deteriorate operational stability of the electroniccomponent and damage associated electronic equipments. A heat sinkattached to a top surface of the electronic component is required toremove heat therefrom.

Typically, the heat sink comprises a solid base and a plurality of finsarranged on the base. The base is attached to the electronic componentso as to absorb the heat. However, only a part of the base, usually amiddle part, contacts the electronic component. The heat originatingfrom the electronic component is directly absorbed by the middle part ofthe base and cannot quickly spread to other parts of the base. Thisresults in overheating of the middle part of the base, while thetemperatures of the other parts of the base are low relative to that ofthe middle part. The fins on the other parts of the base away from themiddle part are not efficiently used. In order to effectively removeheat from the electronic component, the efficiency of the heat sinkneeds to be improved through sufficient use of all of the fins on thebase.

Accordingly, what is needed is a heat dissipation device with anenhanced heat dissipation performance.

BRIEF DESCRIPTION OF THE DRAWINGS

Many aspects of the present embodiments can be better understood withreference to the following drawings. The components in the drawings arenot necessarily drawn to scale, the emphasis instead being placed uponclearly illustrating the principles of the present embodiments.Moreover, in the drawings, like reference numerals designatecorresponding parts throughout the several views.

FIG. 1 is an isometric, assembled view of a heat dissipation device inaccordance with an embodiment of the present disclosure.

FIG. 2 is an exploded view of the heat dissipation device of FIG. 1.

FIG. 3 is an inverted view of the heat dissipation device in FIG. 1.

FIG. 4 is a partially exploded view of the heat dissipation device inFIG. 3, with a heat absorbing block separated therefrom.

FIG. 5 is a cross section view of the heat dissipation device takenalong line V-V in FIG. 1.

DETAILED DESCRIPTION

FIGS. 1-3 illustrate a heat dissipation device in accordance with anembodiment of the present disclosure. The heat dissipation device isprovided for removing heat from a heat-generating component such as anelectronic component, more specifically a central processing unit (CPU)of a computer. The heat dissipation device comprises a base 10 and fingroup 20 arranged on a top of the base 10.

The base 10 includes a conducting plate 12 supporting the fin group 20thereon, a retaining bracket 14 fixed to a bottom surface of theconducting plate 12, a plurality of heat pipes 16 located between theconducting plate 12 and the retaining bracket 14, and a heat absorbingblock 18 received in the retaining bracket 14 and in contact with theheat-generating component.

The conducting plate 12 is a rectangular, thin plate and made of copperwith a heat conductivity better than that of aluminum. Two restrictingflanges 122 extend upwardly from two opposite edges of the conductingplate 12 and restrict the fin group 20 placed on a top surface of theconducting plate 12 therebetween, whereby the fin group 20 can be morefirmly positioned in place. Two pairs of spaced through holes 120 aredefined in the conducting plate 12 and all located at a front half ofthe conducting plate 12 for fixing the retaining bracket 14 to thebottom surface of the front half of the conducting plate 12.

The retaining bracket 14 is integrally made of a metal such as aluminumwhich has a density smaller than copper. The retaining bracket 14 has arectangular retaining plate 140 engaging with the bottom surface of thefront half of the conducting plate 12. The retaining plate 140 defines aplurality of elongated receiving grooves 144 in a top surface thereofand a rectangular opening 142 in the center thereof. The receivinggrooves 144 are perpendicular to and near front and rear sides of theretaining plate 140, and are arranged side by side and parallel to eachother. The receiving grooves 144 in the front side of the retainingplate 140 are spaced from the receiving grooves 144 in the rear side ofthe retaining plate 140 by the rectangular opening 142. Four retainingsleeves 146 extend downwardly from four corners of the retaining plate140. Four retaining rings 148 extend upwardly from the four corners ofthe retaining plate 140 and are respectively in alignment with the fourretaining sleeves 146. Four receiving holes 1460 are respectivelydefined in the four corners of the retaining plate 140 through thecorresponding retaining rings 148 and the retaining sleeves 146, forreceiving respectively four fixtures 100 therein to mount the base 10onto the heat-generating electronic component.

The heat pipes 16 each are flatten and have a flat upper surface and aflat lower surface. The heat pipes 16 have first portions juxtaposed toeach other and second portions bent form the first portions so that thesecond portions are spaced from each other. A distance between twoneighboring second portions gradually increases along a direction fromthe first portion toward the second portion.

The heat absorbing block 18 is rectangular and made of copper with aheat conductivity better than that of aluminum. The heat absorbing block18 is constructed to be fitly received in the opening 142 of theretaining bracket 14.

Also referring to FIGS. 4 and 5, in assembly of the base 10, the topsurface of the retaining bracket 14 is engaged with the bottom surfaceof the front part of the conducting plate 12. The retaining rings 148 ofthe retaining bracket 14 are received in the corresponding through holes120 of the conducting plate 12 and have top surfaces coplanar with thetop surface of the conducting plate 12. The upper surfaces of the heatpipes 16 are all attached to the bottom surface of the conducting plate12 by adhering or soldering. The first portions of the heat pipes 16span over the opening 142 of the retaining bracket 14 and are receivedin the corresponding receiving grooves 144 of the retaining bracket 14.The first portions of the heat pipes 16 are sandwiched between theconducting plate 12 and the retaining plate 140 of the retaining bracket14. The second portions of the heat pipes 16 extend divergently from thefirst portions of the heat pipes 16 to be attached to the bottom surfacethe rear half of the conducting plate 12. The bottom surfaces of theheat pipes 16 cooperatively define a flat contacting surface in theopening 142 of the retaining bracket 14 to enable the heat pipes 16 tointimately contacting with the heat absorbing block 18. The heatabsorbing block 18 is received in the opening 142 of the retainingbracket 12 and has a top surface in intimately contact with thecontacting surface of the first portions of the heat pipes 16 and abottom surface lower than the bottom surface of the retaining bracket 12for contacting the heat-generating electronic component.

The fin group 20 placed on the top surface of the conducting plate 12comprises a plurality of fins 22 spaced from each other andperpendicular to the conducting plate 12. Four cutouts 24 are defined intwo opposite lateral sides of the fin group 20 for facilitating thefixtures 100 to extend downwardly into the receiving holes 1460 of theretaining bracket 14. The fins 22 are perpendicular to the tworestricting flanges 122 of the conducting plate 12 and have flanges 220extending perpendicularly from top and bottom edges thereof. All of theflanges 220 are arranged in succession to cooperatively form a top flatsurface and a bottom flat surface of the fin group 20. The flat bottomsurface of the fin group 20 is placed on the base 10 and in intimatelycontact with the top surface of the conducting plate 12.

Due to an appropriate arrangement of the heat pipes 16 between theconducting plate 12 and the heat absorbing block 18, heat generated bythe heat-generating electronic component during operation can be quicklyabsorbed by the heat absorbing block 18 and transferred to theconducting plate 12 via the heat pipes 16, and then distributed over thefin group 20 through the conducting plate 12 to dissipate into ambientenvironment. The base 10 has a higher efficiency than a conventionalsolid base made of aluminum or copper in transferring heat from theheat-generating component to the fin group, for the heat absorbing block18 and the conducting plate 12 both being made of copper with betterheat conductivity than aluminum and connected to each other by the heatpipes 16. The heat pipes 16 use a phase change of working fluid totransfer heat which has an efficiency much higher than that achievableby a metal block which uses a conduction to transfer heat. In addition,the base 10 is much lighter than a solid base made of copper since thebase 10 consumes a relatively less amount of copper for constructing thebase 10.

It is believed that the present embodiments and their advantages will beunderstood from the foregoing description, and it will be apparent thatvarious changes may be made thereto without departing from the spiritand scope of the invention or sacrificing all of its materialadvantages, the examples hereinbefore described merely being preferredor exemplary embodiments of the invention.

1. A heat dissipation device adapted for removing heat from aheat-generating component, comprising: a base comprising a conductingplate, a retaining bracket attached to a bottom surface of theconducting plate, a plurality of heat pipes having first portionssandwiched between the conducting plate and the retaining bracket, and aheat absorbing block embedded in the retraining bracket; and a fin grouparranged on a top surface of the conducting plate of the base andthermally connecting therewith; wherein the heat absorbing block has atop surface in contact with the heat pipes and a bottom surface adaptedfor being in contact with the heat generating component.
 2. The heatdissipation device as claimed in claim 1, wherein the heat pipes havethe first portions arranged closely side by side and second portionsbent from the first portions, the second portions being spaced from eachother and a distance between two neighboring second portions graduallyincreasing along a direction from the first portions toward the secondportions.
 3. The heat dissipation device as claimed in claim 2, whereinthe heat pipes have flat top surfaces all in contact with the bottomsurface of the conducting plate.
 4. The heat dissipation device asclaimed in claim 1, wherein the retaining bracket defines an openingtherein and a plurality of receiving grooves in the top surface thereof,the receiving grooves being divided into two groups which are spacedfrom each other by the opening and located at two sides of the opening.5. The heat dissipation device as claimed in claim 4, wherein the firstportions of the heat pipes span over the opening and are received in thereceiving grooves and cooperatively define a flat contact surface bybottom surfaces thereof, the flat contact surface being in the opening.6. The heat dissipation device as claimed in claim 5, wherein the heatabsorbing block is received in the opening of the retaining bracket withthe top surface thereof in contact with the flat contact surface of theheat pipes.
 7. The heat dissipation device as claimed in claim 1,wherein the conducting plate and the heat absorbing block are both madeof copper, while the retaining bracket is made of aluminum.
 8. The heatdissipation device as claimed in claim 1, wherein the retaining bracketis engaged with the bottom surface of a front half of the conductingplate and has four retaining sleeves extending downwardly from fourcorners thereof.
 9. The heat dissipation device as claimed in claim 8,wherein four rings projecting upwardly from top ends of the retainingsleeves are received in four through holes defined in the conductingplate, the rings having top surfaces thereof coplanar with the topsurface of the conducting plate.
 10. The heat dissipation device asclaimed in claim 9, wherein four fixtures are received in the rings andsleeves for securing the base onto the heat-generating component. 11.The heat dissipation device as claimed in claim 10, wherein the fingroup defines four cutouts corresponding to the four through holes ofthe conducting plate and comprises a plurality of fins spaced from eachother and perpendicularly arranged on the conducting plate.
 12. The heatdissipation device as claimed in claim 1, wherein two restrictingflanges extend upwardly from two opposite lateral sides of theconducting plate and restrict the fin group therebetween.
 13. A heatdissipation device adapted for removing heat from a heat-generatingcomponent, comprising: a base comprising a conducting plate, a retainingbracket attached to a bottom surface of the conducting plate anddefining an opening therein, a plurality of heat pipes having firstportions arranged side by side closely and sandwiched between theconducting plate and the retaining bracket and second portions bent fromthe first portions away from the retaining bracket in a divergentmanner, and a heat absorbing block received in the opening of retrainingbracket having a top surface in contact with the heat pipes and a bottomsurface adapted for being in contact with the heat generating component;and a fin group arranged on a top surface of the conducting plate of thebase and in thermal connection therewith.
 14. The heat dissipationdevice as claimed in claim 13, wherein the heat pipes have flat topsurfaces all in contact with the bottom surface of the conducting plate.15. The heat dissipation device as claimed in claim 13, wherein aplurality of receiving grooves are defined in the top surface of theretaining bracket, interrupted by the opening and located at two sidesof the opening.
 16. The heat dissipation device as claimed in claim 15,wherein the first portions of the heat pipes span over the opening andare received in the receiving grooves and cooperatively define a flatcontact surface at bottom surfaces thereof, the flat contact surfacebeing in the opening.
 17. The heat dissipation device as claimed inclaim 16, wherein the heat absorbing block is received in the opening ofthe retaining bracket with the top surface thereof in contact with theflat contact surface of the heat pipes.
 18. The heat dissipation deviceas claimed in claim 13, wherein the conducting plate and the heatabsorbing block are both made of copper, while the retaining bracket ismade of aluminum.